Ok so the rules say nothing that isn't from a japanese game/anime I get that much. But what if I do a character who is japanese from assassin's creed? They have a japanese branch of the assassins and I wanted to do Hattori Hanzō but since assassin's creed is made by a french company would it not be allowed?

If you could find artwork of something like that, AND if the base character was still recognizable as such, that would probably qualify. The tricky part is the “recognizable” bit. When it comes to fan designs and so forth, the Masquerade staff look over the proposed costumes and make a decision based on whether or not we feel the character is still recognizable. So in your example, we would need to be able to look at Goku in his Kratos outfit and be reasonably sure that anyone else who looked at it would know that it was GOKU in the outfit.

I will say however that this is skirting the rules and getting awfully close to the line. Trust me when I say that we on cosplay staff aren’t trying to be hardasses, here - we love seeing non-anime cosplay as much as everyone else. But we need to try to stay as close as possible to the Anime Boston mission statement, and a line needs to be drawn SOMEWHERE.